Goldman Sachs is back in pole position to win the takeover battle for Britain's biggest ports operator, Associated British Ports, after lifting its offer for the business another 8% yesterday, to £2.8bn.

The Wall Street firm increased its offer after a shoot-out with rival bidder Macquarie Bank of Australia late on Thursday. Macquarie issued a statement yesterday urging AB Ports shareholders not to take any action while it considered its next move. The Goldman-led consortium, Admiral Acquisitions, said it had agreed a deal with the AB Ports board at 910p a share in cash. That was a significant premium on its former agreed offer of 840p.

Shares in AB Ports were trading at 917p yesterday, suggesting that the City thinks there could still be acts to play out in the bid drama.

AB Ports runs 21 ports in Britain including those at Southampton, Plymouth and Hull and handles about one quarter of the country's seaborne trade. Once considered a less than glamorous business, ports are now seen as prized assets against the backdrop of rising global trade. AB ports has the added attraction of thousands of acres of disused dockland around the country that could be sold for redevelopment.

The auction has delighted the AB Ports board led by Bo Lerenius, the chief executive, which had first agreed to be taken over by Goldman Sachs at the price of only810p a share less than two weeks ago, before Macquarie appeared.

"Clearly the Goldman consortium has demonstrated how extraordinarily keen they are to secure AB Ports and the issue is: are Macquarie as keen?" asked Gerald Khoo, an Oriel Securities analyst. "Management describe the offer as fair and reasonable. I would describe it as bloody fantastic."

The latest round of bidding was set off after Macquarie approached AB Ports on Thursday and said that it was ready to put an offer on the table. The Australian bank had spent the past week trawling though AB Ports' books after indicating that it was prepared to at least match the 840p offer from Goldman. The AB Ports board responded by telling both sides to come up with their best deals. It was unclear how much Macquarie bid.

The price clearly proved too much for one of Macquarie's consortium partners, the British venture capital firm 3i, which yesterday withdrew from the bidding. Sources claimed that the Macquarie consortium could still proceed without 3i.

Goldman is keen to win AB Ports after being involved in a string of failed bids for ITV, the airports operator BAA and pubs group Mitchells & Butlers. It has agreed a break-up fee of £28m if AB Ports decides to walk away from the deal.

The Wall Street firm's consortium is 33% owned by the Canadian pension fund investment arm Borealis and 33% by the private equity arm of the Singapore government, GIC. Goldman owns 23% and the remaining 10% is owned by the Prudential Group. The British port operator P&O was bought earlier this year by Dubai Ports World for £3.9bn, sparking a political row in the United States where P&O managed six ports.

DP World solved the crisis only by agreeing to hand over management of the American ports to a US company. In Britain there has been little equivalent handwringing about the prospect of foreign companies controlling the nation's ports. Mersey Docks and Teesport have also been bought over the past year.

Macquarie has become an increasingly familiar name in Britain and yesterday agreed a deal to buy bus company Stagecoach. It also owns a stake in Bristol airport, was among the early bidders for BAA and made an audacious bid for the London Stock Exchange.